Has anyone checked out Prospect Tube yet? It's a collecting site for minor league player videos. I think it's fairly new, but is building steam very quickly.
For example, here's some video of Jhoulys Chacin. You'll notice some other Rockies prospects videos also easily accessible.
Just beware, that since individuals are posting them, there's no common identifiers for the videos, so a Search on "Rockies" or "Colorado" for example, may not get you all the Rockies prospects.
It's great stuff.